16 BOVINE PATHOLOGY. 



various secretory or other tissues. The modes of death 

 are in reality as numerous as the possible modifications of 

 the various factors of life ; but they all end in stoppage 

 of the circulation, and the withdrawal from the tissues of 

 their internal medium" (Foster). 



The following methods of death may be remembered : 



Death from ANiEMiA, due to cessation of blood-supply, 

 as after profuse haemorrhage. The symptoms observed in 

 such cases are running down pulse, respirations irregular, 

 pallor of visible mucous membranes, coldness of extre- 

 mities and of general body-surface, which may be bedewed 

 with cold sweats ; dilatation of the pupil, and loss of 

 sensibility of the retina ; loss of voluntary power, and, 

 finally, convulsions. The first vital organ which fails in 

 this case is the brain. The recumbent position, therefore, 

 tends to prolong life by mechanically keeping up the supply 

 of blood to that important organ. 



Transfusion of Blood has been successfully resorted to 

 in such cases in man. It is a dangerous operation to the 

 healthy animal from which the blood is taken. It has 

 been accomplished experimentally in the lower animals by 

 connecting the carotids of two individuals by a tube, such 

 as an ureter (Percivall). Thus, it has been proved that 

 the blood must be from individuals of the same species. 



Death from Necr^mia occurs in blood diseases where 

 the vital fluid has lost the stimulating power by which it 

 excites the heart to action, as a result of putrid decom- 

 position. 



Death by Asthenia is sudden cessation of the hearths 

 action, and may be due to poison or shock, as in 

 lightning injury. After death the right side of the heart 

 is found to contain venous and the left arterial blood. 

 This form of death is also known as syncope, but this 

 term is generally also applied to anaemic death. Asthenia 

 sometimes occurs gradually, then the pulse becomes irre- 

 gular, and the blood supply to distant parts of the body 

 is defective. This culminates debilitating disorders. 



Death by Asphyxia has been elsewhere described. 

 Ajpnoea does not cause death, it accelerates life. 



